Add basic support to semihosting (#384) #237

Job	Run time
Build Website	32s
Build (ubuntu-latest)	40s
Build Examples (espressif/esp)	2m 26s
Build (windows-latest)	1m 40s
Dry Run Packaging	43s
Build Examples (gigadevice/gd32)	2m 17s
Check that stm32 generated code is up to date	2m 45s
Build (macos-latest)	45s
Build Examples (microchip/avr)	2m 10s
Build Examples (microchip/atsam)	2m 13s
Unit Test Ports (ubuntu-latest, gigadevice/gd32)	29s
Build Examples (nordic/nrf5x)	2m 8s
Unit Test Regz (ubuntu-latest)	56s
Unit Test Ports (ubuntu-latest, raspberrypi/rp2xxx)	36s
Unit Test UF2 (ubuntu-latest)	31s
Build Examples (nxp/lpc)	2m 7s
Unit Test Regz (windows-latest)	2m 26s
Unit Test Ports (ubuntu-latest, stmicro/stm32)	24s
Unit Test UF2 (windows-latest)	1m 16s
Build Examples (stmicro/stm32)	42s
Unit Test Regz (macos-latest)	42s
Unit Test Ports (windows-latest, gigadevice/gd32)	1m 17s
Unit Test UF2 (macos-latest)	34s
Build Examples (raspberrypi/rp2xxx)	2m 25s
Unit Test Ports (windows-latest, raspberrypi/rp2xxx)	1m 12s
Unit Test Ports (windows-latest, stmicro/stm32)	1m 42s
Validate Foundation Libc (ubuntu-latest)	26s
Unit Test Ports (macos-latest, gigadevice/gd32)	33s
Validate Foundation Libc (windows-latest)	1m 14s
Unit Test Ports (macos-latest, raspberrypi/rp2xxx)	36s
Validate Foundation Libc (macos-latest)	28s
Unit Test Ports (macos-latest, stmicro/stm32)	36s
	39m 31s

Provide feedback